1. Field of the Invention
The present invention relates to a slide-type input device, a portable device provided with the input device, and a method and medium of using the input device, and more particularly to a slide-type input device, a portable device provided with the input device, and a method and medium using the input device, which can move a pointer displayed on a screen and more conveniently and exactly select a specific object.
2. Description of the Related Art
Portable devices such as a cellular phone and a personal digital assistant (PDA) are usually provided with an input device called a pointing device. A user of the portable device can move control objects such as a cursor, a pointer, and others, by operating the pointing device.
In case of the portable devices, a pointing device, which moves the control objects using input keys (direction keys) in the plane of a display screen, has been widely used. The pointing device detects a key input operation by the user, and converts the detected key input operation to a movement control command for controlling so that the control object can be moved in the plane of the display screen.
There has been greatly increased a need to be able to freely move the control objects in any direction, because applications of the portable device perform multiple functions. However, the pointing device using the direction keys has not been designed on the assumption that the control objects are to move freely in any direction. Therefore, the pointing device using the direction keys has a disadvantage in that it is not possible for the control objects to be moved in an arbitrary direction on the display screen.
Pointing devices, by which the control object can be moved in an arbitrary direction on the display screen, include stick type pointing devices such as a joy stick, a touch pad, a track ball, a track pointer, and others.
However, in small and thin portable devices, it is not desirable that the pointing device, in which a lever protrudes from a surface of a cabinet, be built in the portable device, respectively. Further, even if the protruded lever is short, the operation ability of the user is decreased, because the length of the lever is short.
Further, the touch pad has the disadvantage that additional equipment (e.g., a stylus pen) is required. The track ball has the disadvantage in that the portable device becomes larger. In addition, pressure operated track points are inconvenient.
Japan Patent Unexamined Publication No. 2004-062447 discloses a point device of a mobile terminal including a rim having a circular shape, a center key configured to be movable in an arbitrary direction of an xy plane, and Hall elements configured to detect the direction and amount of movement of the center key in the xy plane, which can enable a user to operate in an arbitrary direction (i.e., at an angle of 45 degrees) within the rim using the center key.
However, Japan Patent Unexamined Publication No. 2004-062447 measures a location of the central key on the xy plane by detecting the change of a magnetic flux density using the Hall elements.